Parallelism
by Koroe
Summary: After the late Pharaoh refuses to duel him, Seto Kaiba uses the Quantum Cube to travel between parallel dimensions and scour for a living version of his rival. In one, he encounters a woman far too similar to the one in his visions, yet critically absent from all other worlds, including his own.
1. Stage One: Shock I

**A/N:** This story follows DSOD, therefore it follows the manga, _not_ the anime. Otherwise, Seto Kaiba wouldn't be so emo.

 **Extended Summary:** Silent about what happened in the afterlife, Seto Kaiba immediately returns to the mechanic comforts of his technology in order to fuel further plans for the Quantum Cube. In the mere span of one month, he continually isolates himself in his space station and singlehandedly finds a way to use the Cube in order to transport himself between dimensions of the same world, hoping to find a reality with a breathing Pharaoh. Seto's reckless impatience with finding his rival will hatch its own consequences, and it will take a deranged journey of multiple universes for him to come to terms with his grief disguised as a malignant desire of supremacy.

But he won't be alone. Enter a resourceful woman with familiar white hair and eyes of blue whose being can only be calculated to exist in one reality. She proves to be valuable and her longing to escape her current life makes her the ideal travel companion - ideal in the manipulative sense that he could use and discard her later for his own gains. That is to say, if his growing fondness for the unfortunate woman doesn't sway his mind.

* * *

 **Stage One: Shock I**

Some people experience out-of-body sensations as an initial response to loss.

" _Until your heart weighs less than Ma'at's feather, you are unable to face me in this afterlife. Only then will you cease this futile pursuit, and open your eyes past Ammit's jaws. You may return when you've found and embraced the **light** for that gnawing darkness you cling to."_

Dull cobalt eyes struggled to peak open as harsh blue light was the first to greet Seto Kaiba's weary awakening. Soft pillows and crisp cotton bedding were replaced by hard steel for his lying head and swivel chair for his body. To think by now, he would have installed a bed of some sort in his otherworldly domain - a highly identifiable Kaiba Corporation satellite in dead space linked by means of tubular elevator to Earth. However, he _knew_ that if he had a bed right there, it would coax him into a much needed and unwanted slumber, and impede his urgent research.

If the Pharaoh would not have him, then Seto would find an alternate solution, one to satiate his primal cravings of triumph, victory, dominance, and all words associated. His late rival's Ancient Egyptian jargon would occasionally slip into his short episodes of light sleep, fading away into a meaningless void as soon as he awoke. He had a stubborn will and the brains to find a way to circumvent the Pharaoh's wish, and the Quantum Cube glowing in brilliant bursts of golden light in his hand held all his answers.

"MOKUBA KAIBA IS ON CALL."

The A.I. of his space station announced in a volume loud enough for Seto to clearly lift his lids. He glanced toward a large screen projection above several computers and weakly said, "Accept."

The concerned face of his thirteen year old brother appeared. How different did those violet eyes of his brother appeared to be. Now on the cusp of adolescence, Mokuba Kaiba had the faintest signs of growth. He looked rather tired, rivaling the state that Seto was currently in, and was dressed in pajamas speckled with little cartoon dragons.

"Seto...when are you coming back down?"

"If today is a success, then soon," Seto wryly answered.

"Are you eating properly? You look sick," Mokuba commented as the area between his eyebrows continued to wrinkle together, "It's like 3:42 A.M."

"There are no time zones in space," Seto replied. He wasn't lying. Time no longer functioned as it did on Earth, where it was marginalized as a human construct, and the only light he experienced closely was from the blue light of his devices. He asked, "Hold on, what are _you_ doing up at this hour?"

Mokuba's eyes lowered, avoiding Seto's interrogating glare. He softly responded, "I can't sleep. Not when I know what you're about to do…not when you refused to return even after the previous trip. It's been too long, Seto. I-I support you in any way but-"

"I'm sorry, Mokuba," Seto firmly declared, yet not a trace of sincerity seemed to be given. It was an apology out of convenience. He couldn't hear anymore from his little brother, lest the guilt overcome his main objective. He continued, "But this is something I have to do."

"Sometimes I feel like," Mokuba's eyes flashed forward, and his face contorted into one of near anger. That brief glint of frustration dialed into one of submissive acceptance. Once again, a look of anxiousness emerged.

"It was like _I watched you die_ …" Mokuba sputtered as he recalled not only a month ago he watched his brother fade into abstract light with undetermined return, "And you're thinking of going back...I can't bring myself to see that again!"

"I'm not going back _there_ ," Seto corrected, "The risk of my death is substantially less for this one."

"That's a lie! This journey isn't any less dangerous than the last one...you don't even know one hundred percent what can happen. Seto, you didn't even tell me what happened the first time! And those threats about starving yourself to death if we sent up a person instead of microwave dinners and ramen boxes...even if that person was _me_..." There was a subtle crack in Mokuba's voice as the boy exclaimed in rasps. His voice grew softer and he pleaded, " _Please_. Come back before you kill yourself."

"If I have returned from the _afterlife_ , then I can certainly from this. Do you trust me, Mokuba?" Seto listlessly said. He wouldn't have it. Not when he was so close again.

A defeated look settled across Mokuba's face as he reluctantly answered, "I always have."

"You're in charge."

"I know."

And with one click, Seto severed the remaining connection between himself and his only relative.

The dismal silence that fell afterwards gave him a moment's reflection. Mokuba had repeatedly declared that he wouldn't see him off this time, in hopes that Seto would retreat. Seto didn't entirely believe him at the time, but his little brother had kept his word. Despite living alone for the past month, bereft of any human connection, only now did he feel loneliness in its truest form.

* * *

One look at the swirly mass of azures, emeralds, and milky white clouds in the expanse of planet Earth was enough to make Seto sick. He had finished showering, dressing, and eating in preparation for his journey. As he peered through the expansive windows of his space station, he once again wrapped a hand around the Quantum Cube, letting its self-emitting warmth act as reassurance for his actions. Soon, the sun would pervade Japan.

He had lied. His return to the real world had nothing to do with his own technology and everything to do with the Pharaoh's obscure powers. There was no guarantee he could be back again, but that was a fact best kept to himself. With a sharp turn of his heel, Seto briskly walked away from the sight of Earth. He wouldn't have any of the Pharaoh's rejections and none of his useless advice. He would find him in more ways than one. Even if it meant that death's hands were wrapping around his neck, the remnants of his defeat in Battle City that had plagued his head and evolved into a monster was more terrifying than death itself. It was all worth it in the end.

Blinking lights and various displays automatically came to life as Seto entered one of numerous testing facilities. He unwaveringly strode toward the center of the machine-infested room, where a single pod speckled with a plethora of buttons and controls was awaiting. Once he had placed the Quantum Cube in its respective slot, the pod came to life, and its cover opened as a haunting greet. He wasted no time to situate himself within the pod, settling into the comforts of a cushioned seat.

"Multiverse Dimension System activate!"

In the blink of a millisecond, reality crumbled around him, and his body was no exception to the shocking pulses of disintegration. Unlike the previous time, he could suddenly feel physical pain seer through his skin, invade every cell, and tear apart the smallest atom. Nuclear. It was certainly torture on a nuclear level, incomparable in pain to any scar on his back and arms. His eyes, even if they felt like they could pop out at any moment, widened to a ghastly radius as his mouth did the same and released a blood curdling scream that no one in millions of miles could hear as he plummeted straight down to Earth. Every fiber in his body melted into a flurry of cadmium ambers and golds, as far as his eye could see, and for the briefest of moments, wailing roars as far as his ears could hear.

* * *

Bits of wet pebbles scraped against his cheek as he felt his face come forth with the texture of rocky gravel. His tongue managed to accidentally roll out and taste the grime of tar and trash. It smelled like the city, the one Seto temporarily forgot the name of as the neurons in his brains struggled to return to normalcy, but it was a stench that could make his stomach forgo ten meals. Faint sounds of sirens and cars honking that indicated typical city traffic could be made out in the distance. His hands quivered as he attempted to push himself up. Even with his eyes tightly shut, he was accursed by visions of electric sparks and kaleidoscopic shapes. The aftershock of dimension travel was significantly more taxing, as he even noticed that the smell of burnt ashes wasn't coming from surrounding garbage, but from himself. He didn't factor in safety measures after how rushed everything was, and that was perfectly predictable.

After multiple efforts, Seto managed to have his feet on the ground. His right hand grasped his left arm, the one that usually held his duel disk. His head and back remained low, as if there was something weighing him down. His eyelids fought gravitational force as he tried to lift his head, shaking at every degree. One tentative foot reached forward. The mere pressure of having it resettle with the ground sent unparalleled pain signals to his brain as he winced his eyes back shut.

 _No. I can't stop now. I will find you, **Pharaoh**. Even if I have to cripple myself. _

Stubbornness that trademarked Seto's persistence regenerated energy as he fought against each painful step. He had to get somewhere because staying still led him nowhere. Amongst the cacophonous sounds of the city, his ears suddenly focused on what sounded like footsteps ahead. They were quick and indicated running strides, and they hit the occasional puddle that could be identified with mushy sounds of flying water. And then, he could swear that they stopped. His nearly defeated eyes cracked open as he himself paused his steps.

Light softer than one from the screens of his devices accumulated to one focal point in what he assumed to be blurry lines of a dark alley. Pipes and electric lines became one, and he could make the faintest silhouette of what appeared to be a glowing figure a couple feet away, saturated by a beam of natural light. His eyes squinted to make out the person's identity as his right hand released his arm to hold over his eyes.

"It can't be..." a silvery, feminine voice softly remarked from the light, "Dead men can't walk."

Before his lips could part, his knees gave away first, and the sheer impact of collapsing against the unforgiving ground was absolutely inconceivable.

...


	2. Stage One: Shock II

**Stage One:** Shock II

 _Denial is the greatest grace._

Her thin, bony fingers beckoned her to outstretch toward the kneeling, abysmal figure of the stranger as her feet lightly sauntered towards him. Brown locks of hair fell above his widened eyes. Subdued blue irises constricted in light of his recent pains, and his front teeth visibly clenched a bleeding bottom lip, as if to suppress a wounded howl.

But before the tips of her fingers could grace his forehead to confirm his being, the man released hold of his lip and jerked his head up. His sudden movement, like a hissing cobra in front of a mongoose, caused her to quickly retract her arm.

"Don't touch me!" he snarled, although he was in no position to say so brusquely.

One foot of hers trekked back, yet her sights remained focused on him. He appeared to be putting in immense effort into placing himself upright, and his shallow breaths were ever so audible. Her hands twitched, gesturing her to aid him, but she paid greater heed to his wish.

"Are you real?" she breathed out as he achieved his full height, a good head above hers. Quickly, however, his head drooped lower as he brought one hand to his forehead, covering one eye of his. His eyebrows were harshly muscled together as his previously gaped eyes reduced to squinting ones.

"I could ask the same of you!" He lashed out like he had used up the majority of his dwindling energy in one breath. He clumsily took steps toward her, and her feet led her back the closer he got. Blue eyes. Unruly white hair. Simplistic facial features. All variables in an equation he couldn't decipher in his current state of mental disturbance.

"It is you who is dead," she meekly responded as the two fell into a dance of stepping forward and back, "If you are who I think."

"Then who am I?" He commanded more than asked as he stopped. His hand released his head, revealing the one uncovered eye.

She stopped as well. Her eyes dropped to his attire, taking in the obnoxiousness of his silver trench coat emblazoned with "KC" on the collar. From neck to toe, he was completely covered, save his hands poking from metal bands, like handcuffs. He was perfectly identifiable and perfectly infamous in the city. The magenta dyed innards of his trench coat were enough as a signature to his identity. She looked back up towards a face filled with displeasure and confusion - one that intently studied her own.

"Seto," she supposed in a muted tone as she hesitantly licked her lips before even more quietly completing, "Kaiba."

"Then you know not to stand before me," he simply said.

But not even his animated breaths and words could convince her of his existence. Her hand once again lifted, but she was entranced to target his chest instead, to feel for a beating heart.

"I only know by that name that you don't belong in this world," her voice accompanied her hand, but she was briskly paused by Seto's, which encased her frail wrist. He tugged her hand upwards, motioning her to look up towards his face.

"I meant for you to _get out my way_ ," he strongly instructed. Without wasting a second, he roughly pulled her wrist aside, causing her to stumble forth sideways. She managed to catch herself on her feet as he walked past her. Her eyes widened in surprise at his crude action, and her mind was sent into a state of deja vu in response to her skillful save - an instinctual move.

Before he could escape the reaches of the alleyway, she turned around and called out, "There are people everywhere. They won't take kindly to your appearance."

He abruptly paused. One hand curled into a fist, veins lining leading up into his sleeves. He owed her no explanation, but her reasoning begged several questions.

"How can I believe your word?" He questioned out loud with his back remaining to hers, "That I am dead."

"There is a corner store that sells newspapers and TVs," she mentioned as she approached him. Once she stood by his side, she continued, "With your name written and spoken."

"How am I going to get to said store if you say everyone will question me?" He looked over to her unbothered face as he attacked her lapse in judgement.

She only looked ahead, toward the street with cars and people and the brilliant world.

"I will get you an article."

For a brief second, he wondered why she would go to such lengths for him, and he would make it vocal as to why. He asked, "Why do you care?"

"I've got nothing to do or lose," she easily reasoned. Without hearing back, she left.

* * *

Seto leaned against the alley's walls as he felt another wave of nausea hit his body. He looked toward his wrist, expecting a watch to be there. He forgot he had gotten rid of it. It was unfortunate because it felt like that woman had left eons ago and he had no sense of time, rendering him in a frustrated state of unknowing. He felt himself slide down, letting the coarseness of the wall rub against the back of his head and his coat subject to minor tears and scratches. Once his bottom landed on the ground, he let out a pathetic sigh. He spread his hands out in front him and stared at them like they would be gone in a second.

" _Suppression is the weakest form of acceptance. But you know that well enough, do you not?"_

"I've got nothing to suppress or accept," he blurted to himself.

" _Kaiba may not but Seto does."_

"Hnngh!" he squeezed his eyes shut as he buried his aching head into his hands, feeling his heart beat in faster increments. His mouth hung open to capture ragged breaths of air as his nose kept clogging from the putrid smells of waste.

"Here," the same silvery voice from before appeared.

Seto removed his hands from his face to look up to her looking figure. Her face remained expressionless. There was no trace of pity in her tone or appearance, and for that he was silently grateful. She held out a rolled newspaper, to which he accepted.

She then knelt down, leveling herself to his position. He took it back. She did pity him.

"What is your name?" He demanded.

She ignored his question as she placed a grocery bag in the area between them.

"I asked you a question."

Her eyes lifted to his as her hands paused from scrunching around the bag. Her lips pursed, as if she had to think extensively over such a common question.

"They say it's Kisara," she answered as she pulled out a couple items to which he ignored to continually stare at her blank face. It was like she didn't care about her name, as if it was an afterthought.

Her mannerisms were peculiar to say the least. She had this air of apathy, but not the haughty kind he held. Before he could probe impending questions regarding her odd response, she unexpectedly slapped a plain black baseball cap over his head.

"Y-you!" He sputtered in shock as she single-handedly delivered one of the most offensive motions anyone had dared to perform on him. His hand immediately reached for the lid of the cap, but before he tossed the accursed hat away, he felt her hand on top of his.

" _You_ need to stay low, right?" She asked.

He smacked her hand away, choosing to ignore her. In swift motions, he looked down and flew through newspaper articles of The Daily Domino.

 _ **FAREWELL MR. KAIBA**_

 _The official funeral for Seto Kaiba will occur on the 8th of May and will be held in the old Kaiba Manor. According to Kaiba Corporations' intel, it will be a private affair with only those closest to the late CEO._

 _I wonder who those are,_ he inwardly snickered.

Before he could read on, another article distracted his detailed eye.

 ** _YOUNGER KAIBA FINALLY SPEAKS OF ELDER'S DEATH_**

 _Mokuba Kaiba reveals future plans for Kaiba Corporations, and-_

That was enough for Seto to scrunch the newspaper shut. Suddenly, whatever nausea had hit him beforehand became minute in scale to the one that intoxicated through every pore of his body shortly after.

"I got this as well," Kisara spoke up. She displayed a generic, long-sleeved grey shirt. She added, "I suggest you take off that coat of yours. It's ghastly. That tight black shirt is just a macho display for your six-pack too. I don't think you want me to start on those kink straps and devices on your arms and legs."

Seto lifted his cap to get a better look at her and to fully toss her a dirty glare. Frankly he did know his attire wasn't excluded from opinions, but she was the first to openly criticize him in such detail.

"You haven't got a filter, do you?" He incredulously mocked.

"I've got nothing to lose from not having one," she coolly shot back.

"You've got a life," he cynically implied.

"Not much of one," she despondently retorted as she shrugged her shoulders.

Seto silenced for a bit after that reply. Curioser and curioser. Not only were her responses fueled with self-deprecating tones, but her appearance started to register unwanted familiarity. There was something about her glaringly obvious yet he couldn't place a damn finger upon.

"For your information…" Seto argued, "This coat of mine is highly capable of deflecting both bullets and fire. This device running down alongside my left arm is capable of utilizing my Solid Vision technology-"

"Both of those must be capable of attracting everyone a mile away from you too," she absentmindedly interjected as her eyes ran down his glowing blue Duel Dimension Focus arm and bracers, ignoring his ridiculed glare.

"Did you just-" He stopped short from picking another argument. It was trivial.

"How much was all this?" He changed subjects and started readying himself for his wallet.

Kisara blinked, trying to search for an appropriate answer to explain her less than legal acquirement of said items. She decided, "You can pay me through your story."

"I only have cash on hand," he snorted.

"Well I didn't waste a cent so you can't repay me with that," she partially confessed.

"What do you mean you-" his eyes widened in realization as to what she was implying, "...then it would be even more logical if you accept my money. I assume you have nothing if you had to steal cheap items."

"I have no value in money. Just your story," she firmly concluded as she further inched the grey shirt closer to Seto's face.

He let one hand feel the soft fabric, but he didn't pull it toward himself. The tip of his tongue didn't want to offer anything detailed to Kisara.

"I am looking for someone," he mentioned as he pulled on the shirt.

Kisara didn't let go. The two remained at a crossroads. She remarked, "That isn't a story."

"It is the only one you need to know."

"Then I'll help you find that someone," she stated.

Seto raised both his eyebrows at the blatant tone of her statement. It was almost translated as sarcasm if it wasn't for her serious face. With one sharp tug, he confiscated the shirt from her fingers. He rose, battling only dulled pain.

"I work alone."

He undressed his jacket, thoughtlessly throwing it to the side.

"Then you will die alone," she murmured as she closely watched him. He didn't seem to hear. When he took of his coat, she could more clearly recognize his visible muscles. She more audibly stated, "Even someone as fit as you can't seem to survive what pain you went through."

"You need to be fit if you are to travel through dimensions," he blandly replied as he unlocked his metal wrist cuffs. He focused on his arm straps next.

"Is that more of your story?" She peered, "That you really are not of this world?"

"I believe you've already figured that out," he lazily mused as he finished releasing his straps and machinery that ran alongside his left arm. His eyes went down as his fingers started to grasp at the bottom of his black turtleneck. He caught her intrigued gaze looking up toward him. It was slightly creepy.

"...Do you mind?"

Kisara only cocked her head and replied, "You seem quite proud to show off your body with how tight that shirt is. Why stop now?"

Crazy. A lunatic she was. He scoffed as he couldn't tell if she was being true to her curiosity or if she was a rabid fan girl. Either way, he was seldom comfortable stripping in front of anyone. His throat went dry as he peered at the shirt she had given him. He was grateful that she had not chosen one with short sleeves.

"Just because I'm not a part of this world, doesn't mean I don't have basic human rights to privacy," he shot back.

"I suppose."

Kisara lifted herself from her crouched position and turned her back on Seto. He let out another scoff before saying, "You're a little too close."

She took approximately five steps ahead.

He shook his head. The faster he changed, the better. His fingers wavered as they laced black fabric, pulling the bottom from the hold of his pants. He took one big breath before quickly pulling his shirt up. As quick as he wanted the process to be, the cool, morning air creeping along the surface of his skin produced a sense of unwanted vulnerability that caused time to momentarily cease. He couldn't remember a time he had ever been so open in the breeze of the outside world. Only the comforts of his shuttered bedroom were privy to the secrets engraved against his skin.

"This someone must be special to you," she wistfully said, "Must be nice."

Her clear voice shattered his train wreck of jumbled thoughts and was sufficient to set him on the right track. He quickly exchanged his black shirt for the grey one, desperately pulling it over his head. It was comfortable and fairly loose, appropriately tight around the arms but not enough in the chest to expose his abdominal muscles. He crouched down to retrieve his machinery.

The clinking and clunking of his devices caused Kisara to assume, "Are you done?"

Seto ignored her question as he finished assembling his creations. He went back to answer her previous sentiments once he managed to walk in front of her.

"He isn't special," he corrected and lowly growled, "He just needs to be humiliated by the crushing defeat of my own hands. I've come from far to find him, and I'm not about to give up now. He ran away from my world because he was _scared_ , and then he ran away a second time when I found him, but he is a fool to try and escape from inevitable defeat that Seto Kaiba will inflict upon him." He balled his fist into one hand, knuckles white and nails digging into his palm, and thrust it towards the empty air.

Kisara blankly stared at his dramatic motion and monologuing, unable to register his seriousness. His face was stone yet his movement and speech were otherwise jokes.

"Oh boy," she breathed softly. Her bottom lip trembled as she lifted a hand to her mouth, but before she could completely set her palm against her lips, a thunderous howl escaped her esophagus. The other hand grappled her stomach as she nearly fell over in a fit of inescapable giggles that rendered her stomach acids to flux in unparalleled amusement, and she shut her eyes, embracing foreign laughter.


End file.
